Insulation on top of wool insulation

My attic is insulated with wool. Not having any idea just how good that
performs I had a mind to augment it with the pink stuff. But I'm wondering
if I can just roll it on top of the wool, or should I remove the wool first.
If I do, removing it will be a job I'd just as soon not do - I'd rather pay
higher bills than do something like that. The other issue for me is that
they covered up all the wires with the wool, so I don't have a clue where
they are and that makes my job of re-wiring just a bit more difficult - as
normally I would just clip the old stuff and run the new Romex through the
hole left by the bad stuff as it dropped into the wall. But that adds a
different question - in the attic, is wiring exposed/insulation cut around
it like is done in a wall, or does the insulation cover it?

Well unfortunately there isn't a vapor barrier under the wool, just the
sheetrock.
Does wool even provide decent R values or what. I've heard rumors that it
works relatively well - we're talking 4 to 5 inches of the stuff in the
attic.

EV-
Your blow-in rock wool is about comparable to fiberglass roll (per
inch basis)
http://www.coloradoenergy.org/procorner/stuff/r-values.htm
you've got about R12 to R15
what is recommended for your area?
Even SoCal attics now get R30......Twenty five years ago I did R30 & I
thought it was overkill, now its city code.
JMHO blow-in is easy & cheap compared to fiberglass batts or rolls
BUT if you ever have to work in the atttic.......blow-in sucks
Blow-in cellulose is comparable to blown rock wool & fiber glass
batts; fiberglass blown is lower
cheers
Bob

except if the ceiling 'rock is 1/2", then fiberglass may be the better
option because it weighs less and is less likely to crack the 'rock. Yeah,
fiberglass isn't as good an insulation as cellulose, but the ceiling weight
issue is definitely something to consider.

I just covered the blown-in insulation with unfaced fiberglas batts. The batts
are nice when you need to work up there, for wiring, etc, because you can move
them aside easily and then replace them.
Do not insulate knob and tube wiring, if that's what you have. I replaced all
that in my attic before insulating. It could be wirth investigating your wiring
before adding insulation.
Bob

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